Plasma Exchange for Transplantation-Associated Thrombotic Microangiopathy in Stem Cell Transplantation From an Hla-Mismatched Family Donor

Abstract

Objective: HLA-mismatched stem cell transplantation (SCT) from a family donor using steroids for graft-versus-host disease (GVHD) prophylaxis is useful in refractory hematological diseases, but is associated with many complications.The purpose of this study was to investigate the efficacy of plasma exchange (PE) therapy for transplantationassociated thrombotic microangiopathy (TA-TMA) in patients with HLA-mismatched SCT. Methods: Between October 2016 and September 2021, we retrospectively evaluated 22 patients who developed TA-TMA and received PE after HLA-mismatched SCT from a family donor. Results: Median age was 36 years. Twenty-one patients were in a state of non-remission, and 4 patients had a 2-HLA-haplotype mismatched family donor. For GVHD prophylaxis, tacrolimus plus methylprednisolone was administered to all patients. PE was effective in 15 patients (68.2%), and duration from the onset of TA-TMA to PE initiation was slightly shorter in these cases. Three patients developed heart failure during PE, although this was reversible. The 100-day and 1-year survival rates were 50.0% and 9.1%, respectively. Conclusion: PE may be effective and safe for TA-TMA after allogeneic HLA-mismatched SCT.